Retractable ripper tooth



United States Patent RETRACTABLE RIPPER TOOTH Homer T. McCrary,Davenport, Calif.

Application May 27, 1955, Serial No. 511,640

7 Claims. (Cl. 37-145) This invention relates-to a ripper tooth, andmore particularly to a ripper tooth adapted for mounting on a bulldozerblade.

As is well known in the art, ripper teeth are used for breaking up harddirt or clay, commonly referred to as hard pan, digging out rocks, rootsand the like, or performing other jobs which a bulldozer or similarequipment cannot adequately perform or which would tend to injure thebulldozer blade or such other equipment.

It is an object of the present invention to provide a ripper tooth whichis vertically adjustable so that the action of the tooth on or relativeto the ground may be better controlled.

Another object of the invention is to provide a ripper tooth of thecharacter described which may be readily raised and lowered intoselected positions of vertical adjustment without requiring any manualeffort.

A further object of the invention is to provide a ripper tooth as abovedefined which is adapted for mounting adjacent the rear surface of abulldozer blade whereby the respective individual or combined functionsof the tooth and blade may be available on a unitary piece of equipment,and in which the tooth may be selectively positioned in an operative orinoperative position.

A still further object of the invention is to provide apparatus of thecharacter described in which the ripper tooth is positioned relative tothe bulldozer blade so that the slope or gauge of the earth may bereadily controlled.

' Yet another object of my invention is to provide a ripper tootharrangement which is positively locked in selected positions of verticaladjustment and which may be readily released to permit movement of thetooth to such positions.

The invention possesses other objects and features of advantage, some ofwhich, with the foregoing, will be set forth in the followingdescription of the preferred form of the invention which is illustratedin the drawing accompanying and forming part of the specification. It isto be understood, however, that variations in the showing made by thesaid drawing and description may be adopted within the scope of theinvention as set forth in the claims.

Referring to said drawing:

Figure 1 is a side elevational view of the front end of a bulldozerequipped with the ripper tooth of the present invention.

Figure 2 is a rear elevational view of the ripper tooth.

Figure 3 is a cross-sectional view taken substantially in the planeindicated by line 33 of Figure 1.

Figure'4 is a front elevational view diagrammatic in character of abulldozer blade and associated ripper t qt The ripper tooth of myinvention, generally indicated by the numeral 6 in'the drawing, is shownand will be described in cooperative relationship with a bulldozer andits blade 7, but it will be apparent that the tooth 2,912,774 PatentedNov. 17, 1959 structure could likewise be positioned on a separate pieceof moving equipment, such as a tractor or the like, without departingfrom the scope of this invention.

One of the reasons for providing the tooth on a bulldozer is to permitthe combined action of the normal tooth functions and those of thebulldozer. Heretofore when a ripper tooth was mounted on a bulldozerblade, the tooth was fixed in position with the lower end thereofextending below the lower edge of the blade. With the tooth attached insuch a manner, it is impossible to utilize the bulldozer blade for itsnormal operations without first removing the tooth. Thus, as will bepresently described, the tooth 6, although carried on the blade 7, iscapable of being raised and lowered relative to the blade so that it maybe lowered into an operative position when the tooth is to be used, andconversely raised into an inoperative position above the lower edge ofthe blade when conventional bulldozing operations are to be eifected.

As here illustrated, the tooth is mounted on the rear surface 8 of thebulldozer blade 7, and is preferably constructed of a modified I-beamcross-sectional form. The form offers large strength, and permits theforward curving of the lower end 9 of the tooth at the low stresspoints. Also, as will be presently explained, this construction lendsitself particularly well to the means for supporting the tooth as wellas for locking the same in selected positions of vertical adjustment.

The tooth, with the exception of the curved lower end 9, issubstantially vertically disposed with a leading edge flange 12, acentral web 13, and a trailing edge flange 14. The upper end of the webmay be provided with an aperture 16 which permits engagement of thetooth by a hook or the like in installing or removing the tooth from thebulldozer.

Extending rearwardly from the blade 7 is a pair of support plates 21 and22 disposed in parallel spaced relation to each other, said plates beingprovided with directly opposed lugs 23 for fitting into the recessesformed between the flanges and web on each side of the tooth. As will beclear from Figure 3 of the drawing, the lugs are positioned tosubstantially prevent all but vertical movement of the tooth andactually serves as a guide for such movement.

The drawing illustrates the tooth in a lowermost position, with thelower ripping end thereof positioned substantially below the lower edge26 of the blade 7. The tooth is What might be termed in operativeposition so long as the distal end 27 thereof is lower than the bladeedge 26. When said blade end is vertically higher than such edge, thetooth serves no function and will not interfere with the normal uses ofthe bulldozer blade, being completely hidden behind the same. However,the vertical spacing between the blade edge 26 and the tooth tip 27,when the tooth is in operative position, is most important, as thecontrol of the spacing may be utilized to gauge or control the groundslope by using a combination of tooth vertical adjustment and its fixedhorizontal spacing from its adjacent tip 29 of the bulldozer blade. Thislatter use is illustrated in Figure 4 of the drawing.

In accordance with the foregoing, means are provided for selectivelyvarying such vertical spacing from zero to the maximum shown in thedrawing, and for positively maintaining the tooth in such selectedpositions. Obviously, any hydraulic system could be utilized for raising and lowering the tooth, but as the illustrated environment for thetooth includes a bulldozer blade which is itself vertically adjustable(as is well known in the art), I prefer to utilize the verticalm'ov-ability of the blade to provide the means for raising and loweringthe tooth This is accomplished by virtue of the sliding fit between 3the lugs 23 and the tooth. Thus, assuming the tooth tip 27 is resting onthe ground, and in absence of any locking means which will be presentlydescribed, raising of the blade will leave the tooth stationary andincrease the vertical spacing previously discussed. Contra movement orlowering of the blade will reduce such spacing.

In association with the foregoing, means are provided which secures thetooth to the blade at selected positions of relative verticaladjustment. As here shown, the rearmost edge of tooth flange 14 isformed in the nature of a vertically extending rack 31 having the usualalternate teeth 32 and sockets 33. A latch member 34 is arranged tocooperate with the selected teeth and sockets therebetween, and isformed of a pair of generally vertical parallel arms 36, pivotallyattached adjacent their lower ends to the support plates 22 and 23 bymeans of a pin 37. The upper ends of the arms are secured together by across bar 33, the latter having a cross sectional form permitting it tomesh in selected ones of the rack sockets 33. Thus, with the latch 34positioned as illustrated in the drawing, the interfitting of the bar 38thereon will positively resist any movement of the tooth relative to theblade. A spring 39 having one end connected to the upper end of one ofthe arms 36 and its other end connected to the blade 7 serves toyieldingly maintain the latch in its rack engaging position.

To insure such engagement, I provide a latch lock 41 in the form of abell crank, one arm 42 thereof having a hook-like projection 43 forengagement with a latch lock lug 44 mounted on plate 21. The arm 46 onthe other side of a pivot pin 47, by means of which the lock 41 ispivotally attached to the latch 34, is normally urged in acounterclockwise direction (as seen in Figure l) by a spring 48, so thatthe projection 43 will engage the lug 44.

Thus, it will be seen that by virtue of the springs 39 and 48, the bar38 will engage the rack, and will be maintained in such position byaction of the interengagement of the latch lock projection 43 and lug44.

Means are provided to effect a release of the latch lock and latch so asto permit tooth movement relative to the blade. Such means includes apiston 51 actuated through a hydraulic conduit 52. A piston rod 53 ispivotally connected to latch lock arm 46 by a pin 54, and release of theparts is effected in the following manner. Extension of the piston willmove the latch lock in a clockwise direction about its pivot 47 untilthe arm 46 engages a stop lug 56 carried on latch arm 36. This movementis sufiicient to release the latch lock from lug 44. Further pistonmovement results in counterclockwise rotation of the latch 34 about itspivot 37 and disengagement of its cross-bar from the tooth rack.

From the foregoing, it will be understood that if the blade 7 and tooth6 are both in a raised position, piston actuation will permit a gravitaldropping of the tooth. Release of hydraulic pressure at any time willpermit the springs 39 and 48 to return the latch and latch lock to theirnormal locking position and hold the tooth in fixed relation to theblade.

What is claimed is:

1. Apparatus of the character described comprising a longitudinallyextending ripper tooth, a pair of relatively fixed vertical memberspositioned substantially immediately adjacent opposed sides of saidtooth restricting lateral movement thereof, means on said membersrestricting lateral planar movement in a direction normal to said firstmentioned movement, a rack gear provided on one end surface of saidtooth, a latch member, means pivotally attaching said latch member tosaid fixed members, means normally urging said latch member intoengagement with said rack gear, and fluid actuated means operable todisengage said latch member from said rack gear.

2. Apparatus as set forth in claim 1 in which said tooth is of agenerally I-shaped cross-sectional form, and said fixed members and saidmeans thereon are seated within the opposed surfaces of said tooth.

3. Apparatus as set forth in claim 1 including a latch lock normallymaintaining said latch member in rack gear engagement, and in which saidfluid actuated means upon operation first releases said lock from saidlatch member prior to moving the latter out of rack gear engagement.

4. Apparatus of the character described comprising a longitudinallyextending ripper tooth, a pair of relatively fixed members positionedadjacent opposed sides of said tooth restricting lateral movementthereof, means on said members restricting lateral planar movement in adirection normal to said first mentioned movement, a rack gear providedon one end surface of said tooth, a latch member, means pivotallyattaching said latch memher to said fixed members, means normally urgingsaid latch member into engagement with said rack gear, a latch lockhaving a pair of normally disposed arms and pivoted intermediate saidarms to said latch member, a first lug carried on one of said fixedmembers and engageable by one of said latch lock arms, a second lugcarried on said latch member adjacent the other of said latch lock arms,and means for rotating said latch lock about its pivot to disengage saidfirst lug and eflect engagement of said second lug for rotating saidlatch member to release the same from said rack gear.

5. Apparatus as set forth in claim 4 including spring means for urgingsaid latch lock into engagement with said first lug.

6. In a bulldozer having a generally vertically disposed and movableblade, a vertically movable ripper tooth positioned adjacent the rearsurface of said blade and provided with longitudinally extending groovesin the opposed sides thereof, a guide member mounted on said bladeincluding a pair of elements positioned adjacent opposed sides of saidtooth and having opposed portions extending into said grooves forrelative sliding movement therebetween for guiding said vertical toothmovement and preventing lateral movement of said tooth, rack meanscarried on the rear side of said tooth, a latch member pivotally mountedon said guide member and having a rack tooth engaging element engageablewith said rack means for locking the latter in selected positions ofvertical relationship relative to said blade, means resiliently urgingsaid latch member engaging element into engagement with said rack means,and latch release means operable from a spaced distance from said bladeand said tooth for releasing said latch member from engagement with saidtooth whereby said blade and said tooth may be vertically moved relativeto each other.

7. Apparatus as set forth in claim 6 including means for locking saidlatch member in rack engaging relation, and hydraulic means forreleasing said locking means and moving said latch member out of rackengagement.

References Cited in the file of this patent UNITED STATES PATENTS694,351 Chappel Mar. 4, 1902 1,072,313 Conte Sept. 2, 1913 2,042,196Senz May 26, 1936 2,246,787 Dall June 24, 1941 2,246,793 Dall June 24,1941 2,475,7l0 McCauley July 12, 1949 2,486,372 Rockwell Oct. 25, 19492,657,914 McMahon Nov. 3, 1953 FOREIGN PATENTS 38,000 Denmark Sept. 19,1927 991,748 France June 27, R

